Study investigates effects of insulin treatment during PCI procedure

A new study has investigated if insulin-treated diabetes patients have a risk for adverse cardiovascular events after percutaneous coronary intervention (PCI).
PCI is a non-invasive procedure used to treat a heart condition called atherosclerosis, helping to improve patients’ blood flow.
People with diabetes have an increased risk of cardiovascular problems, and the researchers behind this study report that while insulin-treated patients have a higher cardiovascular risk, these findings often disappear following risk adjustment.
A study team led by Sripal Bangalore, MD, New York University School of Medicine, evaluated 1,830 participants (1,377 of whom were men) from the TUXEDO trial.
These patients were randomly assigned to PCI with a drug called paclitaxel-eluting stents (PES), or another drug called everolimus-eluting stents (EES). 40 per cent of participants were classified as insulin-treated; 60 per cent were not treated with insulin.
The researchers’ primary endpoint was to assess if patients experienced target vessel failure (TVF). This was defined as a composite of cardiac death, myocardial infarctio, or ischemia-driven target revascularisation after one year.
Insulin-treated patients had a higher prevalence of TVF and increased rates of mortality. Non-significantly higher rates of cardiac death were also seen in this group.
The authors wrote: “In patients with [diabetes] enrolled in the TUXEDO trial, those with [insulin-treated diabetes] had significantly worse outcomes compared with patients with non-[insulin-treated diabetes] in the unadjusted analysis.”
However, all of these cardiovascular risks lacked statistical significance once baseline variations between the groups were accounted for.
“This finding was largely attenuated in the propensity score-adjusted analysis, implying that the increased possibility of adverse [CV] events in patients with [insulin-treated diabetes] is accounted for by the differences in baseline risk factors, diabetes duration and [diabetes] control,” said the researchers.
Separate findings of significance included EES leading to more favourable treatment results among the insulin-treated patients, and participants with an HbA1c of 7% (53 mmol/mol) or higher experiencing greater rates of TVF compared to both insulin-treated and non-insulin-treated patients with a HbA1c less than 7%.
The study is published in JAMA Cardiology.